Hoist hook



y 1949- J. E. DOBSON 2,476,847

HOI ST HOOK Filed June 19, 1945 INVENTOR. Jo/zn fiobson Patented July 19, 1949 UNITED STATES PATENT OFFICE HOIST HOOK John E. Dobson, Slippery Rock, Pa.

Application June 19, 1945, Serial No. 600,328

5 Claims.

This invention relates to hoist hooks such as are employed in connection with cranes, derricks, etc., and particularly to that type of hook structure wherein a hook is pivotally supported in a clevis by a pin-and-slot connection whereby, upon vertical movements of the hook in the clevis, the hook can be moved into and out of engagement with a cross bar at the lower end of the hook. In hoist hooks of this form, there is danger that in transporting a load, engagement of the load with an obstruction will cause accidental upward movement of the hook and disengagement thereof from the cross bar at the lower end of the clevis, with consequent danger of injury to workmen, material, or equipment.

The principal object of my invention is to provide a safety device which is readily manipulated, to positively hold the hook in its loadsupporting position in the clevis, but which is movable to release the hook for movement thereof to a load-releasing position.

Another object of my invention is to provide a safety device of the character referred to which, while it is easily manipulated, will not become accidentally moved to a release position, with means thereon for clearly showing to a casual observer whether the safety device is in its operative position or in its inoperative position.

As shown in the accompanying drawing, Figure 1 is a side view of a hoist hook structure showing the safety device in its inoperative position; Fig. 2 is a view showing the safety device in position for holding the hook in load-supporting position in the clevis; Fig. 3 is an edge view of the structure of Fig. 2, and Fig. 4 is a sectional view taken on the line IV-IV of Fig. 2.

The hook structure comprises a clevis 5 having a bail portion 6 for connection to a crane, derrick, or the like, and having a cross bar portion 1 at its lower end. A pivot pin or bolt 8 extends through the legs of the clevis and has a nut 9 on one end thereof. A hook I is positioned between the legs of the clevis and has an elongated hole or slot l2 through which the bole 8 extends. The hook, when not held by the safety device, is movable vertically and pivotally relative to the pin 8, to permit of the lip 13 of the hook being moved out of seating engagement with the cross bar I, to the dash-line position shown in Fig. 1.

A detent l4 of cam-like form is supported between the legs of the clevis by a shaft l which extends through the cam member and is rigidly secured thereto by a tightly driven stud or rivet [6.

When the shaft I5 is rotated to move the detent [4 to the position shown in Fig. 1, the hook l0 may be raised to disengage its lip I3 from the cross bar I and the hook can then be swung clockwise for disengagement of a load therefrom. On the other hand when the detent M is in the position shown in Figs. 2, 3 and 4, it will rigidly hold the hook in its lowermost position, with the lip seated on the cross bar.

The detent I4 and its shaft are rotated by a handle or lever l! which is pivotally connected to one end of the shaftand is of yoke-like form near its lower end, to straddle the nut 9 when in its lowermost position. When the lower end of the lever H is swung clear of the nut, it can be turned about the axis of the pin l5 to rotate the detent, while, when it is in its lowermost position, it will straddle the nut 9 and it, together with the detent I 4, will be held against accidental rotation about the axis of the shaft i5. The lever l1, therefore, also serves as a latch to hold the detent in operative position. If through swinging movement of the clevis, the lever l1 tilts clear of the nut, it will still hang in a substantially vertical position and the detent M will tend to remain in its operative or hook-retaining position. The lever will also serve as a latch to hold the detent in release position, to thereby permit convenient manipulation of the hook.

When the detent is in the position of Figs. 2, 3 and 4, the side of the lever which is exposed will have the legend closed visible thereon and that side may also be painted green to show that the detent is in its safety position. When the positions of the parts |4l1 are as shown in Fig.

' 1, the opposite face of the lever I! will be exposed to view, with the legend opened thereon and that face of the lever may suitably be painted red to show that the detent is in its open or danger position.

I claim as my invention:

1. A hoist hook structure comprising a clevis having a hook-engaging bar at its lower end, a pivot pin mounted in the clevis, a hook having a vertically elongated slot near its upper end, through which the pivot pin extends, and having a down-turned lip that will rest upon the bar, when the hook is in its lower position, the hook being movable vertically relative to the pin and the bar, a cam-shaped detent rotatably mounted in the clevis, on an axis above and parallel to the pivot pin, and engageable with the upper end of the hook, to hold the lip seated on the said bar, at one rotative position, and which at another rotative position will leave sufiicient clearance for upward movement of the hook and its lip to clear the bar, a handle pivotally connected to the detent, on an axis transverse to the axis of the detent, the handle being non-rotatable relative to the detent, about the axis of the detent, and a stop member releasably engaged by the handle, at one side of the clevis, to hold the detent against rotative movements.

2. A hoist hook structure comprising a clevis having a hook-engaging bar at its lower end, a p t pin "mounted 11113118 013Vl 181fh00k having a vertically elongated slot near its upper end, through which the pivot pin extends, and havof the clevis when the handle is swung against the side of the clevis.

4. A hoist. hook structure comprising a clevis having a hook-engaging bar at its lower end, a

5 pivot pin mounted in the clevis, a hook having a 7 vertically elongated slot near its upper end, through which the pivot pin extends, and having a down-turned lip that will rest'upon the bar, when the hook is in its lower position, the hook' 10 *being movable:vertigallvereiativemo the pin and the bar, a-eain"-shaped-*detent rotatabl mounted in the clevis, on an axis above and parallel to the ing a down-turned p a Will rest p r, at pivot pin, and engag eable with the upper end of when the hook is in its lower position, the hook m ltthe hook, to hold the lip seated on the said bar,

being movable vertically relative to the pinandat one rotative position, and which at another the bar, a cam-shaped detentrrotaitably mountewe izotativeamosition will leave suflicient clearance ed in the clevis, on'an axis,above and parallel to the pivot pin, and engageablewith the upper end of the hook, to hold the lip seatedjorrthe, said bar, at one rotativesposition, and which at ani-;,-. other, rotativelposition Will;leave sufiicient clearance iorlupward, movement of, thelhookiand its i l lip to..-c1ear hfil l ashlldle. pivqtally.;connected ",Q, to,th e,detent, on anaaxisiransverse to theaxis of, the 3 detent, "thefhandlel ,being ,-nonrotat,able

tent, ands'a stop ,meinher eleasably engaged by ndetenllhagainstlotatilte movements, the handle h me mova lehby pivotal m ionagainst theside of the clevis,!when the ldetentis in eitherit'shold- ,ing. .or its releasep'osition.

3.[.A' hoisthook structure eomprising 'fa clevis, shav n al ookfingagingubar at its lower; end, a

ll vertically: elongatedsbt near itsnupperlefid, (1Q, throughywhiche 2 7. 6. pivot pinextends, and, having "a.-doWn-tu1nlfe,d lip thatjwillfirest upon the bar,

being, niovable'YerticallY relativeto, the pin and thejoar, a camshapedldetent rotatablymounted we rotative movem-ents'i g the said j -latching ;-means 1 -comprisi-ng-an opening in the free end of the handle, inposition 7to-reeeive ajprojection' at the-side relative .to theedetentnabolitjthe. .aXis or, the dthe handle, at one side'jof, thegclevis, 1m hold the l. I

p vot pin mountedjimtheclevis, a hook having a .when the llooklisiinfits lovgeripos ition, the hook I;

inthe clevis, on an'axis above and parallel to M. for upwardi novement of the hook and its lip to clear the-barre. handle pivotally connected to theedetent, on an axis transverse to the axis of 20 the detent, the handle being non-rotatable relativetq; the detenta about: t he axis of;v the-rdetent;

v nd, ee iem xeael asan lenea eab t s handle at one sideuof, the-,clevisgtdjhold the. de-

ti e indvement the .leiieiibjeing the "clevi 'ganu' in fia d l ll in ol esitionlrelative to. theldetent dvhen the; detent is in either its d n e sr ae fnbsi ll'5lmA'srhdistl'hook structure nomprisingl a clevis a lidol gengaging bafat .itsJowenLend, a

f1, p e i m l fi ed i e he-teen a avin 'a ,5. ivertically elongatedglslot enearr its lupper Tend, ,1 thrqughj iihfch thelpiydt pinlextendsgand havin o atdown-tuiffned 1i .lthafil lwillrestruponnthe bar,

'2 hen l he 11 1, l 1 being: ablewefticallifc relative .lto. theipin and wdetentl nountedjwithin the" clevisland V thelbafla 'le at an outerts'ideiof the "levis for moving,the detent tosanch from itst'hookgh'olding 'positionfiand means toil, releasablyeret'aining. the 7 lever attheloc'ation it occupies when the ,detent 5mml el in iri fiil i 1 TTTJQHNE."'DOB'SON.

."!EFEEEN9 S? tollogvinganeterenees are ton-record .in: the

e tte 7 50 'n" =IESEPRIENTS' hluinber V Name 7 V l ar -Date Q niiz'otalsl notion against thmside of 7 its lower, position thehookrit ip itmmdmm lip seated on 

